For the second straight season, Texas will be without junior quarterback David Ash for a considerable amount of time because of concussion symptoms.

While the absence of an experienced starter under center would certainly impede any team, the loss of Ash could prove to be even more significant for the Longhorns.

Since he took over as the full-time starter as a sophomore, Texas has faired considerably better with Ash in the lineup. In Ash’s 16 starts since the beginning of the 2012 season, the Longhorns have gone 12-4 while averaging 36.6 points per game. Over that same stretch, Texas has scored just 27 points per game while struggling to a 6-5 record without Ash.

The biggest disparity last season, though, came in terms of total offense. In Ash’s three starts in 2013, Texas averaged a whopping 537.3 yards per game, compared to just 370.1 in its 10 games without him. To be fair, the Longhorns racked up a school-record 715 yards against a far inferior New Mexico State team in one of Ash’s game, but they still registered at least 450 yards of total offense in each of the other two contests he started.

One major reason for this discrepancy in offensive output stems from Ash’s ability to limit mistakes and make the most of his pass attempts. His efficiency rating of 153.3 was good for fifth in the Big 12 in 2012, and the 156.3 mark he posted in three games last year would have been good for third best in the conference had he maintained it over the course of a full season. Additionally, Ash has posted an impressive 2.7-to-1 touchdown to interception ratio since becoming the starter in 2012.

On the other hand, backup quarterback Case McCoy struggled to replicate these numbers when pressed into duty last season. In 13 games with 10 starts in 2013, McCoy threw 11 touchdown passes against 13 interceptions, while posting a 109.3 efficiency rating.

While the Texas offense as a whole takes a step down without Ash, nobody seems to experience a bigger drop in numbers than senior wide receiver Jaxon Shipley. In Ash’s 16 starts since the beginning of 2012, Shipley has hauled in six touchdown receptions and enjoyed seven games with at least six receptions. In 11 games without Ash, though, Shipley has recorded just two touchdowns while turning in just three games with six or more grabs.

Sophomore quarterback Tyrone Swoopes gets the start in Ash’s place this week after completing 5-of-13 pass attempts for 26 yards while rushing for 79 yards and a score in limited playing time last year. Texas has had mixed results with quarterbacks making their first career starts in recent seasons; McCoy passed for 168 yards and two touchdowns in a win against Iowa State in 2011, while Ash struggled later that season against Oklahoma State, passing for 139 yards and two interceptions.

The Longhorns hope Swoopes can utilize his considerable size and speed to make an immediate impact after being thrust into the starting lineup, but, as past history suggests, the offense won’t be the same without Ash under center.